Suil is a lightweight C library for loading and wrapping
LV2 plugin UIs.

Suil makes it possible to load a UI of any toolkit in a host using any
other toolkit (assuming the toolkits are both supported by Suil). Hosts
do not need to build against or link to foreign toolkit libraries to use
UIs written with that toolkit; all the necessary magic is performed by
dynamically loaded modules. The API is designed such that hosts do not
need to explicitly support specific toolkits at all - if Suil supports a
particular toolkit, then UIs in that toolkit will work in all hosts that
use Suil automatically.

Suil currently supports every combination of Gtk 2, Qt 4, and X11, e.g.
with Suil a Gtk program can embed a Qt plugin UI without depending on
Qt, and a Qt program can embed a Gtk plugin UI without depending on Gtk.
On Windows, embedding native UIs in Gtk is also supported. I (David
Robillard) would be happy to work with plugin
authors to add support for new toolkits, please contact me if you're
interested in writing a plugin UI using a toolkit that is not yet
supported in the LV2 ecosystem.